Glossary: A-E

A Pillar: A support for the vehicle’s roof located on either side of the vehicle at the very front. The sides of the windshield are bonded to the A pillar.

Accelerated Aging: A set of laboratory conditions designed to produce, in a short time, the results of normal aging. Usual factors include temperature, light, oxygen and water.

Acetic Acid: An acid that can be corrosive to zinc, steel, and other types of aluminized panels.

Acetone: A colorless, volatile, water-soluble, flammable liquid made from either alcohol or by bacterial fermentation of carbohydrates; used in paints and varnishes, as a general solvent, and in chemical manufacturing.

Acrylics: A non-crystaline material with good weather resistance, shatter resistance, and optical clarity; sometimes used for glazing.

Acute Area: The area of the windshield directly in front of the driver's eyes, beginning just above the steering wheel. It measures approximately 8 1/2 inches high by 11 inches wide. This area is used as the standard for the driver's critical vision area by most auto glass shops and insurance companies in the United States.

Adhesion: The clinging or sticking together of two surfaces; the ability of an adhesive to stick to a surface.

Adhesive Failure: Adhesive failure indicated by the material's failing (pulling loose) at the surface of the substrate. This is similar to scotch tape peeling off a plastic substrate.

Adhesive: Any substance that is capable of bonding other substances together by surface attachment. In an auto glass replacement context, it is a high-strength polyurethane material, unless otherwise specified.

Aerodynamics: The branch of physics that deals with the motion of a solid body through air and other gases.

Aging: The progressive change in the chemical and physical properties of a sealant or adhesive.

Air infiltration: The amount of air leaking in and out of a building through cracks in walls, windows and doors.

Air Quenching: Part of the process of tempering glass, when rapid cooling occurs by blowing air onto both surfaces uniformly and simultaneously.

Air Side: The upper surface of the glass; also referred to as score side.

Airbag: A passive restraint system that uses an explosive device to inflate a bag at a high rate of speed. The bag inflates with a gas and then quickly deflates when a vehicle occupant is thrown into it. It is mounted in the steering wheel on the driver's side of the vehicle and in the dashboard on the passenger's side. There are also airbags installed for side impact collisions. Some passenger-side airbags use the windshield to position the deploying bag.

Airspacer: Component placed at the perimeter of an insulating glass unit to separate the two lites of glass.

Alcohol: A broad class of organic compounds. In this context they are industrial solvents that include methanol (used in windshield washer fluid), denatured alcohol (used in glass cutting) and isopropyl alcohol (IPA, used as a cleaning solvent).

Allen Wrench: A six-sided wrench.

Amino Acid Base: A form of chemical cure method of silicone sealant.

Anneal: The controlled process for making glass stronger and less brittle in which the glass is heated and then cooled.

Annealed glass: Standard float glass.

Annealing: The controlled process of cooling glass after manufacturing to strengthen glass and make it less brittle.

Anodizing: A method of coating, coloring and finishing aluminum that both protects and beautifies the aluminum.

Antenna: A conductor that sends or receives electromagnetic waves, consisting commonly of a wire or set of wires. In some late-model vehicles, the radio antenna is incorporated into the windshield or back glass.

Anti-Lacerative Glass: Glass that has a resilient layer of polyvinyl butyral (PVB) added to the inner surface. It prevents passengers from coming into contact with broken glass edges on the inner surface in the event of a collision.

Architectural Scale: A ruler marked in scaled increments that is used to measure a scaled drawing.

Arch-top: One of several terms used for a variety of window units with one or more curved frame members, often used over another window or door opening. Also referred to as circle-heads, circle-tops and round-tops.

Argon: An inert, nontoxic gas used in insulating glass to reduce heat transfer.

Astragal: Center post between two swinging doors.

Auto glass repair: A process that removes air from a break in laminated glass and fills it with a curable, optically matched resin. Synonymous with windshield repair.

Awning: Window with sash swinging outward from bottom.

B pillar: A support for the roof located on either side of the vehicle, directly behind the front seat.

Backbedding: Material or compound used to seal the glass to a window sash.

Backer Rod: A compressible material, either open or closed cell, placed into voids between materials to insulate and allow a backing for the application sealant.

Back-Lite: Passenger car rear window.

Balance: Mechanical device (normally spring loaded) used in single- and double-hung windows as a means of counterbalancing the weight of the sash during opening and closing.

Baroque Pattern: Wire glass where the pattern is square and wires are parallel with the edges of the sheet.

Batch: A quantity of raw materials mixed in proper proportions and prepared for fusion into glass (also called frit).

Bay: A combination of window units that projects to the exterior. Usually features a large center unit with two flanking units at 30° or 45° angles to the wall.

Bead: A sealant or adhesive compound after application in a joint, irrespective of the method of application. A bead looks like a ribbon of adhesive rather than a round drop of adhesive.

Belt molding: A rubber molding between the inner and outer panels of a vehicle door through which the door glass is raised and lowered.

Bezel: A curved, tapered, decorative cover located behind the door latch or in the well of a door pull.

Building Information Modeling (BIM): A 3-D, object-oriented approach to computer-aided architectural design. Enables data for manufacturer's details to be imported right into project design, and presents 3-D models of products in place in building. Also provides access and ability to add to detailed imagery and information to everyone involved in the building process and building operations after project completion.

Bit Brace: A hand tool that is used to drill holes.

Bite: Amount of adhesive overlap between the pinchweld and windshield.

Building-Integrated Photovoltaics (BIVP): A term used for products, such as commercial glazing, with solar-power collection cells built in.

Black Edge: If the backing of a mirror deteriorates, the silver turns black. This condition is known as black edge.

Block (setting): A small piece of neoprene or other suitable material used to position the glass in the frame or opening.

Body Fillers: Compounds used to build up and level low areas that cannot be brought back to their original contour by straightening.

Bond Strength: The force, per unit area, necessary to rupture a bond.

Bond: The attachment at an interface between substrate and adhesive or sealant.

Bottom rail: The bottom horizontal member of a window sash or door panel.

Bow: A combination window that projects to the exterior. Usually features four or more window units in a radial or bow formation.

Box bay: A combination of window units that projects to the exterior. Usually features a large center unit with two flanking units at 90¡ angles to the wall.

Breaking Stick: A stick or other material that is used to place under the score of glass or plastics that assists in the breaking of the material.

Breather tube: Tube placed through airspacer and seal of insulating glass that allows unit to accommodate changes in pressure between time and location of manufacture and time and location of installation, where it is sealed. Usually used to accommodate changes in altitude between plant and job site. Also referred to as capillary tube.

Brickmould: A type of external casing for windows and doors.

Bug: The ANSI insignia on laminated and tempered glass.

Bullet-Resistant Glass: Glass that consists of multiple layers of laminated glass. It is designed to resist penetration from medium- to super-powered small arms and high-powered rifles.

Bull's Eye: Impact damage to laminated glass that is marked by a clean, separated cone in the outer layer of the glass.

Buttering: The application of sealant to the surface of substrate before placing another substrate in position.

Butyl Dam: Butyl Tape Kits have been used as positioning dams. Other terms for a butyl dam are: Sealant Dam, Tape Kit. See Butyl.

Butyl Rubber: A copolymer of isobutene and isoprene. As a sealant, it has low recovery and slow cure, but good tensile strength and elongation.

Butyl: An adhesive used in earlier model vehicles for glass retention. It is a petroleum product that requires no curing or hardening. Butyl is available in rolls of approximately 15 feet. Sometimes called Butyl Tape Kit or Tape Kit. It is available in various thicknesses and shapes.

C pillar: A support for the roof located on either side of the vehicle, directly behind the rear seat. The sides of the back glass can be bonded to the C pillar.

Caming: The metal used in the construction of decorative glass panels. Usually zinc or brass, it is also applied to single glass lites to create a decorative glass look.

Cap Bead: A finished bead applied at the top of an installation.

Capillary tube: Tube placed through airspacer and seal of insulating glass that allows unit to accommodate changes in pressure between time and location of manufacture and time and location of installation, where it is sealed. Usually used to accommodate changes in altitude between plant and job site. Also referred to as breather tube.

Capstock: A material co-extruded with PVC formulated to offer a specific color, finish and/or function, such as heat resistance.

Carbide: A hard binary compound of carbon and a more electropositive element. Used to coat and reinforce the tips of tools to extend the life of the tool.

Casement: Window with sash cranking outward, to the right or left.

Casing: Exposed moulding or profile around a window or door, on either the inside or outside, to cover the space between the window frame or door jamb and the wall.

Catalyst: The substance added in small quantities to promote a reaction, while remaining unchanged itself.

Cell Cast: A method of manufacturing plastics, where molten plastic is poured between two sheets of glass and allowed to cure.

Cellular PVC: Extruded polyvinyl chloride material used in window and door components and trim. Unlike rigid (or hollow) vinyl, it features a foam or cell-structure inside. It can often be nailed, sawn and fabricated like wood.

Cellulosic Composite: Generally, a material combining an organic material, such as wood fiber, extruded with a plastic.

Centrifugal Force: The force that tends to makes an object go outward from a center of rotation.

Channel Tape: A cork and rubber composition material used to secure door glass and to fill channels.

Channel: A piece of U-shaped metal lined with felt used to reduce glass breakage and noise, and to correct alignment of moveable glass parts.

Check rail: The bottom rail on the upper sash and the upper rail of the lower sash of a double-hung window unit, where the lock is mounted. Also referred to as a meeting rail.

Chemical cure: Curing by chemical reaction. This usually involves the cross-linking of a polymer.

China Markers: A wax marker used to mark glass.

Chip: Damage to the surface of the glass not associated with other types of damage. Impact damage to laminated glass that does not penetrate the outer lite. Although glass is missing from the impact point, there is no trapped air in the damage.

Circle Cutters: Cutters that have a vacuum base that attaches directly to the glass. The adjustable arm holds a ruler set to the radius of the desired circle.

Circle-top: One of several terms used for a variety of window units with one or more curved frame members, often used over another window or door opening. Also referred to as arch-tops, circle-heads, and round-tops.

Cladding: Material placed on the exterior of wood frame and sash components to provide ease of maintenance. Common cladding materials include vinyl and extruded or roll-formed aluminum.

Clerestory: A window in the upper part of a high-ceilinged room that admits light to the center of the room.

Clips: Devices which hold decorative chrome to the vehicle body, or hold moldings, and so forth.

Close-Cut or Partial-Cut Installation: An installation method that leaves most of the existing adhesive bead/bed adhered to the metal frame and adds a small fresh bead of adhesive into which to set the glass. Some vehicle manufacturers do not recommend this procedure.

Coated Glass: Glass with a chemical film applied to one surface. The film can provide enhanced performance characteristics such as privacy, solar or mirror effects.

Cohesion: The ability of a sealant or adhesive to hold itself together; the internal strength of an adhesive or sealant.

Cohesive Failure: Adhesive failure indicated by hardened material on both substrate surfaces. The material itself failed (the body of the adhesive or sealant pulled apart).

Combination Break: A break in a windshield involving more than two types of breaks.

Combination Door: A screen or storm door used in combination with a primary door. Storm windows also are referred to as combination windows.

Combustible: Any liquid that will ignite at or above 100°F, but below 200°F.

Compatibility: Refers to the reaction a sealant has on another sealant or on another material.

Composite: A term used for window or door components that consist of two or more materials, such as glass fibers or wood and plastic. The term also is used for windows and doors that combine two or more materials in the frame or sash construction, such as a product with a wood interior and a vinyl or aluminum exterior.

Compress: The act of pressing together or to force into a smaller space.

Compression Gasket: A system that uses a soft gasket on one side of the glass and a firm, dense gasket called a wedge on the other.

Compression Set: Occurs when a sealant is crushed and does not return to its original dimension when the load is removed.

Compression: Pressure exerted on a sealant in a joint.

Condensation: Water vapor from the air deposited on any cold surface that has a temperature below the dew point. Sometimes a problem on cold (and poorly insulated) window glass or framing that is exposed to humid indoor air.

Contaminant: A substance, liquid or solid, which is present in a break. Contaminants must be removed from a break before a repair can begin.

Continuous Cast Plastic: A method of manufacturing plastics, where molten plastic is forced through a machine, then cooled and dried on stainless steel rollers.

Coolant: A liquid used to cool and lubricate glass while it is being cut or ground with a tool to prevent hot spots or fracturing of the glass.

Corner Cleaner: Machine that removes the bead of excess material formed in welding vinyl window corners.

Corrosion: The chemical reaction of air, moisture, or corrosive materials on a surface; also called oxidation. The process of wearing away the surface of a solid.

Cosmetic Blemish: A defect in the appearance of a vehicle. Includes torn upholstery, scratched paint and resin spills.

Cosmetic Surface: A surface that is finished or decorated to improve its appearance. Includes such things as paint, glass and upholstery.

Cottage Double-Hung: A double-hung window in which the top sash is shorter than the bottom sash.

Cowl Panel: A decorative, porous cover mounted to the cowl that covers the lower edge of the windshield.

Cowl: A drain located above the firewall where the windshield wipers deposit rain water.

Crack: An extended crack in a windshield from both sides of an impact point. There are several different kinds of cracks: Short crack: A crack on the windshield of 6 inches (15.24 cm) or less. Long crack: A crack on the windshield of more than 6 inches (15.24 cm).Edge crack: Any crack on the windshield that extends to an edge. Floating crack: Any crack on the windshield that does not extend to an edge. Stress crack: Any crack extending from an edge without an impact point.

Crazing: A phenomena that occurs to plastic when it is exposed to either harsh weatherization, U.V. light or force bending beyond the recommended minimum radius.

Creep: The deformation over time of a body under constant load.

Condensation Resistance Factor (CRF): A rating of a window's ability to resist condensation. The higher the CRF, the less likely condensation is to occur.

Cristallo: An extremely clear glass developed by Venetian glass-makers by adding manganese (as a decolorizer) to the batch.

Critical Path Method: A management technique that breaks complicated processes down to reveal the most direct route to solving or reaching a pre

Cross-Linked: Molecules that are joined side by side as well as end to end.

Crystal: Three-dimensional building blocks that make a substance internally rigid.

Cullet: Broken glass that helps a batch melt more easily.

Cure Time: The time required for a chemical or material to dry or set at a given temperature and humidity. Cure times vary with the type of material used and the thickness of the application.

Cure: The hardening of a liquid material or adhesive by means of a chemical reaction. A process of drying and hardening over a given period.

Curing Agent: A chemical which is added to effect a cure in a polymer.

Curing by chemical reaction: This usually involves the cross-linking of a polymer.

Cut-Running Pliers: Pliers designed for use parallel to the score. The upper jaw has two projections that taper outward from the center.

Cutting Jig: A device used to standardize the cutting of similar size and length materials.

Cutting Rake: The angle and shape of the tip of a cutting tool, such as a drill bit or a saw blade.

Cylinder Glass: Molten glass blown into a cylinder and cut apart, then reheated and flattened.

Cylinder: Subassemblies for a door lock containing a cylinder plug with keyway and a cylinder body with tumbler mechanisms.

Dade County: County in Florida, including Miami, that has set numerous standards and requirements for hurricane-resistant windows and doors.

Dam: A device having a two-fold purpose: 1. A dam cushions and separates the glass from the metal frame where the glass adheres. 2. A dam holds the liquid adhesive and prevents it from flowing into the interior of the vehicle.

Damage: A break in laminated glass. Same as break and crack.

Dauber: A disposable cotton applicator for applying primers and preps to the metal and glass bonding surfaces.

Decorative Glass: Art glass; cathedral, stained, or patterned glass.

De-lamination: The failure of the bond between layers, as when windshield glass separates from the laminate, or when paint peels from the substrate.

Demand Flow Technology (DFT): An approach to analyzing and optimizing production lines.

Desiccant: An extremely porous crystalline substance used to absorb moisture from within the sealed air space of an insulating glass unit.

Denatured Alcohol: Alcohol to which an unwholesome substance has been added to make it unfit for drinking. The denaturing substance does not affect the alcohol's usefulness for other purposes.

Density: The mass per unit volume of a substance under conditions of pressure and temperature.

Design Pressure (DP): A measurement of the structural performance of a window or door. Usually specified as one-and-a-half times greater than necessary based on expected building, wind and weather conditions.

Ding: A non-technical term often used by the public to refer to a stone damage to a windshield or laminated glass.

Divided lites: Separately framed pieces or panes of glass. A double-hung window, for instance, often has several lites divided by muntins in each sash. These designs are often referred to as six-over-six, eight-over-one, etc., to indicate the number of lites in each sash. Designs simulating the appearance of separately framed panes of glass are often referred to as SDLs or simulated divided lites. Designs using actual separate pieces of glass are sometimes referred to as TDLs or true divided lites.

Division Bar: A vertical run channel located between the door window and vent glass.

Door Panel: A decorative panel used to cover the interior panel of the doorframe.

Doorframe: A vehicle part containing an exterior and interior panel that houses the door window and the mechanism used to operate that window.

Dormer: An area that protrudes from the roof of a house, generally featuring one or more
windows.

Double Glazing: Use of two panes of glass in a window to increase energy efficiency and provide other performance benefits. May or may not refer to an insulating glass unit.

Double Seal Units: Insulating glass with two materials used to form the seal of the glass.

Double-Hung Window: Window featuring two operable sash that move vertically in the frame.

Double-Strength Glass: Glass between 0.115 and 0.133 inch thick.

Drag Coefficient: The mathematical expression of the retarding force exerted by air upon a body.

Drilling: The use of a drill to gain access to a tight break.

Drip Cap: Moulding placed on top of the header brickmould or casing of a window frame.

Drop-Jaw Glass Pliers: Pliers used for breaking glass. They have a flat upper jaw and humped lower jaw.

Dry Fit: Process in which a technician sets the glass in the vehicle glass opening before applying adhesive or primer. The process is used to position the glass and mark the position with alignment markings or tape.

Dry Glazing: A method of securing glass in a frame by use of a dry, preformed, resilient gasket without the use of a compound.

Durometer: A blunt probe used to penetrate sealants; measures the hardness from 0 to 100.

Edge Crack: Any crack on the windshield that that extends to an edge. See Crack.

Edge Effect: Heat transfer at the edge of an insulating glass unit due to the thermal properties of spacers and sealants.

Egress Window: Window designed to be large enough for a firefighter to climb in or a person to climb out of in an emergency. U.S. building codes require each bedroom of a home to have an emergency exit window, with minimum sizes specified.

Egress: A path or means of going out of a building or structure, exit.

Elasticity: The ability of a material to return to its original shape after removal of a load.

Elastomer: A rubbery material which returns to approximately its original dimensions in a short time after a relatively large amount of deformation.

Electro-Chromatic Mirror: An interior rearview mirror that senses the glare in oncoming light and automatically dims the vehicle’s high-beam headlights.

Electrochromic Glazing: Glass or other glazing material that can be switched from clear to opaque electronically.

Elongation: A property of urethane adhesive: An increase in length expressed numerically as a fraction or percentage of initial length.

Emery: A granular mineral substance used for grinding and polishing glass.

Encapsulated Glass: A type of auto glass fabrication. Pre-assembled parts that contain hardware: moldings, fasteners, clips, or gaskets. Glass with a decorative molding around all or part of the perimeter. The encapsulation can also act as a channel guide. The molding (encapsulation) is actually part of the glass and can be removed only by cutting it off the glass.

Expansive Cement: An adhesive used to anchor glass railings into a base.

Extensibility: The ability of a sealant to stretch under tensile load.

Extension jamb: A board or trim component that extends from the interior of the window frame to the interior wall. It is used to increase the depth of the jambs of a window to fit a wall of any given thickness.

Extruded Plastics: A method of manufacturing plastics where molten plastic is pulled through a machine called an extruder.

Extrusion Failure: The failure which occurs when a sealant is forced too far out of the joint.

Extrusion: The process, in which a heated material is forced through a die, used to produce aluminum, vinyl (PVC) and other profiles or components used in the production of windows and doors. Term also is used to refer to the profiles or lineals manufactured by this process and used to make window and door components.